Fans of the Hitchhiker’s Guide To The Galaxy series will recognize the name of the car in this ad from the October 5 1951 edition of the Toronto Daily Star:
The Ford Prefect was manufactured in Britain from 1938 to 1941, and then again from 1945 to 1961. It was also manufactured in Canada, where it was built with left-hand drive for Canadian roads.
As for Cedarvale Motors: a search of the Toronto city directories revealed that they changed owners several times. They were at 1463 Eglinton West in 1956 and 1961, and they do not appear in the 1963 directory.